Permanent mold



Feb. l1 l9 J. w. BETTENDORF 1,746,301

PERMANENT MOLD Original Filed May 1?, 1926 5 Sheets-Sheet 1 Feb. 11, 1930. J. w. BETTENDORF PERMANENT MOLD Original Filed May 12, 1926 '5Sheets-Sheet 2 4 Feb. 11, 1930.

Driginal Filed May 12. 1926 J. W. BETTENDORF PERMANENT MOLD 5Sheets-Sheet 5 F 11, 1930- J. w. BETTENDORF- PERMANENT MOLD OriginalFiled May 12. 1926 5 Sheets-Sheet 4 A u J V/ M u l M Q My Feb. 11, 1930.J w, BETTENDQRF I 1,746,301

PERMANENT MOLD Original Filed May 12. 1926 5 Sheet-Sheet 5 L H "Ii-5L1mm 'm 541/00!" to a W he a l bou W43" Patented Feb. 11.1930

PATENT OFFICE JOSEPH W. BETTENDORF, OF BETTENDORF, IOWA PERMANENT MOLDOriginal application filed May 12, 1926,

This invention relates to the manufacture of relatively large steelcastings, such as railroad car side frames, and more particularly-to Ithe mold for making such castings.

This application is a division of my application, Serial No. 108,559,filed May 12, 1926, for the method of making such large steel castings.

Heretofore railroad car truck side frames had'been cast in sand moldshaving baked and green sand cores. The surface of the resulting castingshas ordinarily been quite rough and has been impregnated with particlesof burnt sand. Fins and other surface irregularities have also occurredas a result of the use of sand molds. To prepare such castings for usein railroad cars it has been found necessary to sand blast the surfacegenerally, and

to chip off the surface irregularities, fins, etc.

2 Furthermore, it has been necessary to chip those portions of thecasting which must be of relatively accurate dimensions, such as, forexample, the seats for springs, bolsters and bearings. It may be notedthat such surface finishing has been relatively expensive and hasnecessarily decreased the rate of production of the castings.

It is an object of my invention to east side frames and other intricatelarge steel castings in a metal mold of such construction that the metalof the mold will contact with the exterior of the cast-ing'to formsmooth external surfaces and yet permit the necessary shrinkage of allparts of the castings to prevent cracking or injuring the metal thereof.

' It is also an object of my invention to provide mold members againstwhich may be cast those portions of the inner surfaces of a side. framecasting which need to be of accurate dimension to form seats for partsof the railroad car springs and bolsters.

A further object of my invention is to produce a metal mold for castingside frames or the like in which the cope and drag members are easilyassembled and clamped together, and in which the metal members whichform the inner surfaces of the casting are. readily withdrawableinwardly ,to permit the con? traction of the casting upon cooling. 9These and other objects willbe apparent Serial No. 103,559. Divided andthis application filed October ,8, 1926. Serial No. 140,372.

from the following description and annexed drawings, in which Figure 1is a perspective view of the mold iczlrag with the sand and metal coresin posiion. Y

Fig. 2 is a perspective view of the cope, ready to be set upon the drag.a

Fig.3 is a plan view of th drag with the sand cores and casting metal inhorizontal section; Fig. 4 is a vertical longitudinal section throughthe mold with the sand cores in position, the left half of the copebeing omitted.

Fig. 5 is a view similar to Fig.- 4, with the cope in place and thecasting also shown in sectlon.

Fig. 6 is a longitudinal section through journal box.

Fig. 7 is a transverse view through the gate and central core member.

Fig. 8 is a fragmentary tion through the gate.

Fig. 9 is a transverse section through the portion of the mold in whicha brake hanger is cast.

Fig. 10 is a longitudinal section through the portion of the mold inwhich a brake hanger is cast. a

longitudinal sec- Fig. 11 is a' perspective view of the' 'sand 80 coresassembled for one-half of the main body of the casting.

- Fig. 12 is a perspective View of a casting formed in the mold. Fig. 13is a plan of a modified form of co're for forming the window or largeopening in the casting.

Fig-14 is an elevation of the core structure shown in Fig. 13. i

A form of mold contemplated by my invention is shown generally in the.drawings. The mold as shown is particularly adapted for the casting of arailroad truck side frame 1- which is substantiallysimilar to that shownin Patent 1,351,326, of G. J. WV. Glasen, granted August 31, 1920. Thecasting 1 comprises top and bottom members 2 and 3 and column members 1extending between the members 2 and.3. At each end of the casting areintegral journalboxes 5 and 6 and on one side of the casting areprovided brake hanger brackets 7 and 8. Themembers 2, 3 and 4 define amay rotate.

bolster opening having a top 9, side members 10 and a bottom portion 11forming a spring seat. The said bolster opening is adapted to receivethe bolster and the springs on which the bolster ismounted, as is wellknown inra-ilroad construction.

The mold comprises a cope member C and a drag member D, which membersmay be parted in a median plane of the casting as shown in the drawings,or near one edge of the casting 1. ,After assembly, the mold members maybe maintained'in assembled relation by clamping means (not shown)cooperatively associated with the lugs 12 on the mold members G and D.The exterior surfaces of the casting members 2 and 3 are formed directlyadjacent the inner walls of the cope G and drag D. That portion of themold which forms the exterior I surfaces of' the journal boxes remotefrom the center of the casting is stationary. The portions 13 of thecope and 14 of the drag, however, which form the inwardly facingportions of the exterior of the journal box, must be mounted to moveinwardly so that they willpermit shrinkage of. the ournal box portionsof the casting toward the center thereof. Thus the said portions 13 and14 may be moved toward the center of the mold after the solidificationof said casting and before the complete shrinkage thereof, as

particularly indicated in Figs. 4 and 5, to permit further shrinkage ofthe casting upon cooling, and consequent moving of the journal boxestoward the center of the casting. The members 13 and 14 are shown asindividually moved by similar cam mechanisms. The cope and drag eachcarry pairs of fixed supports, 15 and 16 respectively, and each pair ofsupports carries a cam shaft 17 provided with cam'fingers 18. Themovable portions 13 and 14 of the cope and drag carry projections havingcam apertures in which the cam fingers The ends of the cam shaft arepreferably made square so that they may receive means such as a crank torotate the shafts, and these shafts may be rotated either manually ormechanically. The portions 13 and 14 of the mold members C and D areprovided with cooperative inclined surfaces 13 and 14 so that the saidportions 13 and 14 are moved upwardly and downwardly respectively andat'an angle, and thus the casting is free to shrink toward the center.In

Fig. 5 the members 13 and 14 at the left side of the figure are shown inmolding position while at the right side of the figure they are shownmoved away to permit shrinkage of the casting.

In order to accurately form portions of the inner faces 10 of the columnmembers 4, which define the sides of the bolster openin and to form theinner face 9 of the top mem er so that they will be smooth and accurate1n size, I have provided a plurality of collapsible members and topmembers.

top

preferred form of mounting this core, so that I i the portions may beeasily and quickly moved inwardly after the casting has been poured, isto have them so connected as to be movable by any suitable commonoperating mechanism.

The collapsible metal core to form the inner faces of the column membersmay obviously be of various designs and still be operable by a commonoperating mechanism. I have shown, however, in the drawing a preferredform of collapsible core, which not only forms the inner faces of thecolumn members but a portion of the inner face of the top member, sothat it will also have smooth, accurately sized surfaces.

One form of such mechanism is illustrated herein and comprises the sidemetal core members 25 adjacent which are formed the inner faces 10 ofthe column members 4 and also adjacent portions of the inner face 9 ofthe top member 2. The metal core 26 forms the central portion of theinner face 9 of the top member and overlies the end portions of the coremembers 25. The core members 25 and 26 are provided with inwardlyextending lugs 27 having pins 28 transversely mounted therein. Mountedin the cope and drag is a rotatable shaft 29 having a pair of.

disc members 30 carried thereby for rotation with the shaft. The discmembers 30 are provided with cam slots 31 in which the ends of the pins28 are carried. Upon rotation-ofthe shaft 29 the metal cores are movedinwardly by the engagement of the ends of the pins 28 in. the camslots-81. The cam slots are preferably so designed that the core member26 will initially move inwardly at a greater speed than the-core members25, so

that there will be no interference between the age of the casting.Preferably the core members 25 not only form the inner faces 10 and 9,respectively, but are channel-shaped in cross section so that theyextend over and form part of the outer faces of the column members 4. I

The journal box cores 35 are preferably multi-part sand cores,comprising bottom Metal inserts 36 maybe disposed between said bottomand members to receive threaded ends of handles 37, said handles beinadvantageous in positioning said top mem ers within the mold. The bottommembers may cooperate with apertures in the adjacent drag member toproperly position said bottom members and likewise said metal insertsmay be provided with PI'OjBCtlOIlS cooperating with depressions in saidbottom and top members, whereby said inserts and top members may beproperly positioned within the mold.

In order to form the substantially triangularly-shaped openings in theside frame and also the inner portions of the top and bottom memberswhich are channel-shaped in cross section, suitable sand cores 38 suchas indicated in Figs. 3 and 11 may be employed. Each of the cores 38 isprovided with outer extensions 39 to overlie the journal boxes 5, 6.

The extensions 40, 41 together with the complementary extensions fromthe opposed cores 38 form the opposed portions of the top and bottommembers 2 and 3. Upon both faces of the cores 38 are the core members 42which form the triangularly shaped openings in the side frame. Ifdesired for purposes of ejection of the casting the metallic members 43may be incorporated in the core members 42. If it be desired to obtainsmooth and more accurate inside surfaces of the channel members formingthe triangular shaped openings, this may be accomplished byincorporating the metal members 44 in the cores 42 as shown in Figs. 13and 14.

It is also obvious that other ofthe core members disclosed herein maybeformed, if desired, of metal members with suflicient sandportionsintervening to permit the. proper shrinking of the casting bycrushing the sand Where it is desired to cast brake-hanger supportsintegral with the side frame, the

necessary mold cavity and core forming parts may be disposed within theauxiliary mold portions 45 through a side aperturewhich may be closed bythe doors 46.

In order to orm' a smooth and accurate spring seatll a metal slab core47 is provided,

there being a suitable sand core 48 extending through the member 47 andinto the extensions 41 of the sand cores 38 to provide an aperture 49through the spring seat 11. The sand core '48 is provided with a headportion 50 which forms a spacer for the cooperating sand members 51 and52 through which the gate 53 1s formed. The members 51 and 52 areproperly positioned and locked in place by, the use}? the L-shaped sandcore members 54, which engage the slab core member 47 and engageshouldered recesses 'in' the member 51, as shown in Fig. .1. Bythisconstruction the gate is rigidly projecting pouring cup 55 may be usedif desired.

Underlying themembersfil, 52 are sandcore members 57, 58 which areprovidedwith extensions 59, which extensions project into recesses in.the mold so that the lncoming molten metal will flow 1n streams alongthe passageway 60 and will not have to flow,

held in place and a suitable.

across the metal of the mold until afterits heated or melted due to theengagement with the more rapidly flowing molten metal.

It will thus be seen that the incoming molten metal will flow oversubstantially level sand cores and does not come in contact with themetal mold until the stream has been divided and the direction of flowof each branch changed so that any tendency of the hot metal to overheator wear away the mold is reduced to a minimum.

It will therefore be seen that I have provided a relatively simple,permanent mold structure for molding substantially all of the exteriorsurfaces of a relatively large, intricate steel casting, and that I haveaccomplished this with a metal mold which is relatively exceptionallylight for metal molds for steel castings.

It will be seen that in the embodiment of my invention herein describedthe mass of, the mold, and hence the chilling capacity thereof, isrelatively small. Thus in the present mold the weight thereof is notmuch greater than the weight of the casting. In previous permanent metalmolds for the casting of steel articles the weight of the mold hasordinarily been several times heavier than the article to be casttherein. In the mold herein described, however, the time betweenpourings is ordinarily sufficient to permit the mold to substantiallycool off, and hence I have found the use of a bulky mass of metal moldof large chilling capacity unnecessary.

My mold, therefore, has suflicient chilling capacity for the productionof a casting of fine grain, homogeneous, non-porous structure and toprevent deterioration of the mold .as by melting due to thehightemperature of the casting metal.

It will also be seen that I have provided a relatively simple means forforming the eX- terior surfaces of the casting and yet have madeadequate provision for permitting those inwardly or in the direction ofshrinkage to permit contraction or shrinkage of the metal inthecasting'upon cooling.

To those skilled in the art many modifications of and widely differingembodiments and applications of my invention will suggest themselves,without departing from the spirit and scope thereof. My disclosures andY the descriptions herein are purely illustrative and are not intendedto be in any sense limlt- 'thin section throughout their extent, saidmold having metal portions adapted to contact with a relatively largeportion of the surface of the article to be cast, said mold having metalportions thereof which form inwardly facing interior and exteriorsurfaces of the casting withdrawable before the mold is opened to permitshrinkage of the casting upon cooling, and sand and metal cores to formparts of the casting, and means to move the metal cores inwardly of thecasting before the mold is opened to permit with portions movable aweivshrinkage thereof.

2. A permanent mold for casting relatively large steel castings ofintricate sha e, which com rises, in combination, a separa le metal molrelatively light with respect to the casting, said mold bemg adapted toform substantially all the exterior surfaces of the casting, said copeand drag being provided .from the casting at the places where inwar lyfacingexterior surfaces of the casting occur, so that after the castinghas been poured and before the mold is opened these portions may bemoved to permit shrinkage of the casting.

3. A permanent mold for casting car truck, steel side frames havingcolumns and top and bottom members forming a central bolster opening,comprising a metal cope and a metal drag forming "substantially all theexterior surfaces of the side frame, and metal core members to formportions of the inner faces of said columns and top memberand of theside faces of the columns, said core memhas being movable inwardlybefore separation of said cope and drag to permit shrinkage of thecasting upon cooling.

4'. The invention specified in claim 3, in which movable core membersare provided to form the spring seat.

5. A permanent mold for casting car truck, steel side frames havingcolumns and top and bottom members forming a central bolster opening,comprising a metal. cope and a metal dra forming substantially all theexterior surfaces of the side frame, and metal core members to formportions 'of the inner.

faces of said columns and top and bottom member, certain of said coremembers being I and bottom members forming a contra 1 bolmovableinwardly simultaneously, before the cope and drag are separated, topermit shrinkage of the casting upon cooling.

' 6. The invention specified in claim 5, in

"whichthe core members are movable inward- 1y by common operating means.7. A permanent mold for casting car truck, steel side frames havingcolumns and top ster opening, comprising a metal cope and a metal dragdefining substantially all the exterior surfaces of the side frame andmetal core members to form portions of the inner:

faces of said columns and top, said core mem-g ber forming a portion ofthe top member being movable inwardly ata different rate of speed thansaid side members, said core members being movable inwardlysimultaneously by common operating means to permit shrinkage of thecasting upon cooling.

8. A permanent mold for casting car truck, steel side frames havingintegral journal boxes and brake hangers and having a bolster openingand side openings therein, comu surfaces of the side frame and journalboxes and to form the brake hangers.

[9. A mold for casting car truck, steel side frames having integraljournal boxes, comprising a metal cope and a metal drag to form theexteriorsurfaces of the side frame and journal boxes, the portions ofthe cope and drag forming'the inwardly facing, ex-- terior faces of thejournal boxes being movable away from the casting to permit shrink-" agemovement of the, journal boxes toward the center of the casting, andoperating means carried by the cope to move the portions of the copeforming said inwardly .facing, exterior faces.

10. A mold for casting car truck, steel side frames having integraljournal boxes,

comprising a metal cope and a metal drag to form the exterior surfacesof the side frame and journal boxes, the portions ofthe cope anddrag'forming the inwardly facing, exterior faces of the journal boxesbeing movable away from the casting to permit shrinkage movement of thejournal boxes toward the center of the casting, and operating meanscarried by the drag to move the portions of the drag forming saidinwardly facing, exterior faces.

11. A mold for casting car truck, steel side frames having a bolster.opening, comprising a relatively light metal cope and drag to form theexterior surfaces of the side frame, metal core members adapted to formportions of the inner surfaces of the sides and top of the bolsteropening, a shaft journaled in said cope and drag, said core membersbeing operableto be moved inwardly upon rotation of said shaft.

12. A permanent mold for casting car truck, steel side frames having abolsteropening, comprising a relatively light metal cope and drag toform substantially all the ex terior surfaces of the side frame, metalcore members to form portions of the sides, top and bottom of the sideframe, a bolster open ing, a shaft mounted for rotatable movement. insaid cope and drag, said core members beo ing connected to said shaftwherebyrotation of said shaft causes said core members to move inwardlyto permit shrinkage of the casting upon cooling.

13. A permanent mold for casting a steel article having spaced lateralprojections comprising, in combination, metal mold members arranged tocooperate to define substantially all the exterior surfaces of saidcasting, one, of said mold members carrying metal por- 0 tions arrangedto define inwardly facing portions of said lateral projections, saidmetal portions being movable toward each other directly after thecasting metal is poured and before said mold members are separatedwhereby normal longitudinal shrinkage of said casting may take placereadily without disruption thereof. a

14. A permanent mold for casting car truck steel sideframes havingjournal boxes integrally formed therewith comprising, in combination,metal mold members arranged to define substantially all the exteriorsurfaces of said casting, metal mold portions arranged to define theinwardly facing ex- 36 terior faces of the journal boxes, said metalvportions being movable inwardly toward each other to permit shrinkagemovement of the journal boxes toward the center of the casting, andoperating means carried by mold omember's to move said movable metalportions. k v I In testimony whereof I aflEix my'signature. JOSEPH W.BETTENDORF.

